Container having moveable wall

ABSTRACT

An open-top container or skid having a base, two spaced and parallel sidewalls, and at least one sidewall which is moveable between an upstanding position and a stored position, with the stored position being a position wherein said moveable sidewall lies flat against the base.

United States Patent [22] Filed Oscar F. Mills Grand Prairie, Tex.

[21] Appl. No. 798,959

Feb. 13, 1969 May 25, 1971 LTV Aerospace Corporation Dallas, Tex.

[72] Inventor [45] Patented [73] Assignee [54] CONTAINER HAVING MOVEABLE WALL 8 Claims, 11 Drawing Figs.

[52] US. Cl 220/4 B65d 7/00 Field of Search 220/1, 4, 6, 7, 22, 22.1, 83

[56] References Cited UNITED STATES PATENTS 3,375,830 2/1968 Dixon 220/1X FOREIGN PATENTS 1,100,852 9/1955 France 220/22 1,191,893 10/1959 France 220/6 Primary Examiner-George E. Lowrance Attorney-H. C. Goldwire ABSTRACT: An open-top container or skid having a base, two spaced and parallel sidewalls, and at least one sidewall which is moveable between an upstanding position and a stored position, with the stored position being a position wherein said moveable sidewall lies flat against the base.

PATENTEI] HAYZSIHYI 3580.411

sum 1 or 2 A V aiimi "WW i sf 7 7' 25 FIG 7 Hump OSCAR F. MILLS, INVENTOR WM yw FIG 8 y AGENT PATENTEDMAYZSISH 3580.411

SHEET 2 BF 2 OSCAR F. MILLS, INVENTOR AGENT CONTAINER HAVING MOVEABLE WALL This invention relates generally to skids or containers for transporting or storing a variety of parts having different sizes.

More particularly, the invention relates to a novel gate or partition extending between two fixed sidewalls of a skid or container.

The problem of efficiently handling material and parts within a factory or plant is not new. In those facilities that do not have conveyors for automatically channeling parts and the like from place to place as they are being assembled into finished products, it has long been necessary to provide some means to efficiently move the parts to the work station where they are needed. The ability to move a large quantity of material was greatly improved, of course, with the advent of fork lift trucks, power platform lifts, etc. The versatility of such trucks, however, is sometimes limited by the skids or containers which the trucks can pick up and move from one spot to another. While it has not been hard to design supporting members so that a skid can be picked up by a variety of mechanical lifting or moving devices, it has been difficult to construct a top or superstructure for such skids which could be used to accommodate a variety of materials or parts. That is, it was discovered long ago that in spite of the diversity of designs by different manufacturers in the construction of their mechanical lift trucks, etc., it was possible to design a base which was useable with almost all trucks. The superstructure of such material-handling skids, however, has been typically designed to meet a specific need, and one need only. Thus, if the parts that are to be handled are small, then walls are typically provided completely around the perimeter of the skid to prevent such parts from falling off the skid. If the parts are longer than the typical skid (usually 24 to 36 inches), at least one sidewall must be omitted from the skid so that the parts may extend beyond the periphery of the skid. While the desirability of having a single skid which could serve more than one purpose has been apparent for some time, there has been no suggestion heretofore of a practical way of constructing a superstructure for a skid which would meet thenecds of strength and durability that attend the construction of skids.

The disadvantage of having two types of skids within a factory, namely, skids with sides to accommodate small parts, and skids without sides to accommodate parts that have at least one dimension longer than the base, are readily apparent to those skilled in factory management. For one thing, skids are typically made of heavy gauge (e.g., or I 1 gauge) steel and, like other items of a durable nature, are not cheap. Furthermore, the initial expense of purchasing two types of skids for a factory is but the beginning of expenses directly related to use of such skids; because the time that is wasted by an employee who searches for one type of skid when all he can find are skids of the other type should be directly attributable to the fact that two types of skids are in use. Frequently, employee that are under pressure to meet production quotas will know that a skid of a certain type should be used for their particular material, but if the right skid is not at hand, they are sometimes not conscientious enough to search for the correct skid. Hence, in spite of the fact that proper skids may be available somewhere within the factory, the employee may not avail himself of such skids, and he may attempt to use the wrong skid merely because it is conveniently available. It sometimes happens, then, that small parts fall off skids without sides while they are being loaded or while in transit; too, long parts are sometimes scored or dented when they are laid across an upstanding wall of a completely walled skid rather than laid flat on the base. The damage to production parts that are harmed in this way can quickly mount; but merely having more skids is not always the correct solution to the problem. Thus, having too many skids in a work area can sometimes interfere with production and can constitute a safety hazard.

Accordingly, it is a major object of the invention to provide a superstructure for a skid which is convertible between a configuration without sidewalls to a configuration with sidewalls.

Another object is to provide a convertible skid of the nature described above in which movable walls are permanently attached to the skid so they cannot be misplaced or separated from the skid.

A further object is to provide a skid having at least one movable sidewall which is moveable to a storage position wherein it is not susceptible to being bent, etc.

Yet another object is to provide a skid having a gate or movable sidewall which is supported by the base of the skid when the gate is in its upright position so as to resist deformation as a result of accidental blows.

These and other objects and advantages will be apparent from the specification and claims and from the accompanying drawing illustrative of the invention.

In the drawing,

FIG. 1 is a perspective view of a container having two moveable sidewalls or gates in accordance with the invention;

FIG. 2 is a perspective view of one of the gates as shown in FIG. 1;

FIG. 3 is a cross-sectional view taken in the plane represented by the line III-III in FIG. 1, wherein the gate is in its upright position;

' FIG. 4 is a view of the apparatus shown in FIG. 3 wherein the gate has been moved to a position intermediate its upright position and its stored position;

FIG. 5 is a cross-sectional view similar to FIGS. 3 and 4, wherein the gate has been moved to its stored position;

FIG. 6 is perspective view of a material-handling skid having one moveable wall at one edge of the base and a moveable partition near the middle of the base, wherein the partition divides the base into two portions;

FIG. 7 is a front, elevation view of the partition shown in FIG. 6;

FIG. 8 is a top view of the base shown in FIG. 6;

FIG. 9 is a top view of two exemplary means for connecting a moveable wall to a rigid sidewall of a skid;

FIG. 10 is an enlarged, fragmentary side view of the slot in a portion of the gate, as shown in FIGS. 3, 4, and 5; and

FIG. 11 is an alternate configuration for the slot which is shown in FIG. 10.

With initial reference to FIG. 1, a container 10 having a substantially rectangular platform or deck 11 (FIG. 3) also has fixed, upstanding sidewalls 12, 12A extending from each of two opposite sides of the platform. It is preferred that the sidewall 12A be reasonably high so as to safely envelop a large amount of material; but for the purposes of this invention, it is only necessary that the fixed sidewall be high enough to provide a satisfactory mounting location for pins or studs 14 (to be described). Thus, the wall 12A is much shorter than the wall 12; but it still furnishes an adequate foundation on which to anchor the moveable walls. Furthermore, the walls 12, 12A need not be of uniform height, as indicated by the recess provided in wall 12A. By use of the expression substantially rectangular, it is not intended to narrowly limit this description to rectangles; rather, it is intended to suggest that any shaped base that has at least two corners having included angles of approximately is deemed to fall within the scope of this invention. Thus, if a container is truly square or rectangular, it would obviously fall within the above definition; but a container having an irregular base in which only a portion thereof could be accurately described as rectangular could also incorporate the invention, and should be deemed to be covered by the appended claims.

A gate 13 extends between and is permanently affixed to the two sidewalls 12, 12A by studs 14 having heads 15 which are larger than the widths of the slots 16. The studs 14 are affixed to the sidewalls 12, 12A by means such as welding or by nuts, etc., as indicated in FIG. 9. Each of the gates 13 is selectively moveable between an upstanding position (FIG. 3) and a stored position (FIG. 5), wherein at least the bulk of the gate lies flat against the top surface of the platform 11. An examination of FIG. 5 will reveal that the material being handled may be placed directly on top of the gate 13 when the gate is in its stored position such that the weight of the material is supported primarily by the deck 11 rather than by the gate 13.

-It should be noted, too, that the gate 13 does not extend beyond the base 11 (where it could be easily bent) in the manner that a tailgate typically extends beyond the box or bed of a pickup truck when the tailgate is lowered. This design is advantageous since it will be appreciated that the deck or base 11 is normally designed to be much stronger than a typical sidewall, e.g., sidewalls 12, and it is desirable to take advantage of this built-in strength to support the gate. While the gate 13 is preferably made of steel or other material which is equally as strong as a sidewall 12, it is not necessary with skids of this type that the gate be unusually strong, since much of the load imparted to the gate by material placed thereon is passed directly through the gate to the much stronger base 11.

Referring next to FIG. 2, the gate 13 has a main plate 17 with two ends 18, 18 separated by a distance which is only slightly less than the distance between the two upstanding sidewalls 12, 12A. An end plate 19 is attached to each main plate end 18 so as to be perpendicular to the main plate 17 and hence parallel to the fixed sidewalls 12, 12A. Each end plate 19 has a slot 16 through which one of the aforementioned studs extends when the gate 13 is installed. Referring additionally to FIG. 3, the slot 16 has a configuration which prevents horizontal movement of the end plate 19 when the main plate is in its upstanding position, with horizontal being assumed to be parallel to the base 11. That, is, the stud l4- would resist any potential movement of the end plate 19 in a purely horizontal direction. Referring again to FIG. the slot 16 also prevents vertical movement of the end plate 19 when the main plate 17 is in its stored position wherein it lies flat against the platform 11. Referring additionally to FIG. 4, it will be seen that the slot 16 further has a portion which permits the main plate 17 to be selectively moved between its upstanding and its stored positions by appropriate rotation and translation of the end plates 19 with respect to their associated studs 14. Because the gate 13 is moved upward during transposition between its two normal positions, it is necessary that the top of the skid be open or unobstructed during such transposition. But the top need not be permanently open, so that a cover or the like can be used with the skid. All that would be necessary in such as embodiment is that the cover be moveable so as to provide clearance for the gate 13 during transposition.

Describing the slot 16 more specifically, it has a generally V configuration, with the included angle between the legs preferably being approximately 135 with one leg of the V extending parallel to the main plate 17 and the other leg extending toward the bottom edge 20 of the main plate. The apex of the V is so positioned as to coincide with the longitudinal axis of that stud associated with the slot when the gate 13 is in its upstanding position. With additional reference to FIG. 10, the apex of the slot 16 is separated from the bottom edge of the end plate,l9 by a distance D,, and by a distance D from the main plate 17. Preferably, the distances D and D are substantially equal. The shorter leg of the slot extends in the general direction of the bottom edge 20 of the main plate 17, so that the distance D is made small. The distance D can be less than, but should be no larger than, the distances D,, D and preferably isjust slightly less than said distances. From a comparison of FIGS. 3 and 4, it will be apparent that the distance D determines whether or not the the end plate 19 may be shifted from its upstanding position to its horizontal position and vice versa with relatively little movement. Referring specifically to FIG. 4, it will be seen that if the shorter leg of the slot 16 did not extend toward the edge 20 as far as it does, the end plate 19 could not be rotated from or to its upstanding position, because there would be insufficient clearance between the edge 20 and the top of the deck II. It may be apparent, however, that the configuration of the slot 16 need not necessarily be a true V," as long as the stud 14 could be moved to the terminal position of the shorter leg of the slot as shown in FIG. 4. That is, the slot 16 could have a more nearly L'- shape rather than a substantially "V shape, such as is illustrated in FIG. 11. While the slot of FIG. I] having a substantially L-shaped configuration is functionally I equivalent to that shown in FIG. 10, slightly more material must be removed from the end plate 19 to produce an L- shaped slot than to produce a V-shaped slot. Consequently, an end plate 19 having an L-shaped slot is likely to be somewhat weaker and perhaps less rigid than an end plate with a V- shaped configuration.

Referring again to FIGS. 3, 4, and 5, a lip 23 extends from the top edge of the main plate 17 in a plane other than the plane of the said main plate, so as to advantageously contribute some rigidity to the main plate. To optimize the rigidity imparted to the main plate 17, the lip 23 is made integral with and extends perpendicularly from the main plate. By extending the lip 23 in a direction away from the end plates 19, the lip is adapted to bear against the edge of the platform 11 when the main plate 17 is in its stored position, as shown in FIG. 5.

In this stored position, the lip 23, when subjected to any forces from accidental bumps against loading docks or the like, transmits said forces directly to the platform 11; and because of the slight end clearance provided between the slot 16 and stud l6 and stud 14, no force is transferred to the stud. Hence, there is no tendency to bend the stud 14 to a position where it would be ineffective for its intended purpose, i.e., to serve as a pivot point about which the end plate 19 can rotate. When the gate 13 is in its upstanding position, and the skid 10 is being moved on a fork lift truck, for example, the tines of the truck are normally tilted upward so that the skid leans back against the truck. In this attitude, the bottom edge of the skid typically protrudes slightly ahead of the top, so that upon impact with some obstacle, forces are first transmitted to-and usually absorbed bythe heavy base. In the upright position, then, .the studs 14 are also sheltered from damaging forces due to accidental bumps, etc. It should be noted, also, that the materialhandling skid described and shown is completely devoid of any hinges, which is particularly advantageous since hinges are notoriously susceptible to damage, corrosion, or complete failure. Thus, all of the elements described herein are extremely simple in design, and are as easy to maintain as they are to fabricate. The most sensitive parts of the entire system are the studs 14, and insuring that they are subjected to very littleif any-loading as a result of bumping the skid against walls, other skids, etc., will have a tendency to prolong the life of each stud. Nevertheless, if such a stud 14 should be damaged, it is relatively easy to replace, since as shown in FIG. 9, the studs may comprise a short bolt which is secured to a fixed sidewall by one or more nuts. If the fixed sidewalls are fabricated from corrugated materials, one of the nuts may be tack welded to the exterior of the fixed sidewall, and a second nut used to securely connect the stud to the sidewall. In such a way, the nuts are completely recessed and are not readily subject to accidental damage.

Referring to the embodiment shown in FIG. 6, the gate 13 extends between the two sidewalls 12B, 128 at terminal portions thereof, so as to functionally form a continuation of said sidewalls. As before, the main plate 17 of gate 13 has a bottom edge 20 which engages the platform 118 (FIG. 8) when the main plate is in its upstanding position, so as to inhibit horizontal movement of the main plate toward the interior of the skid 108. The gate 138 extends between the two sidewalls 12B, 128 at a location other than the terminal portions of said sidewalls, such that portions of said platform 11B lie on opposite sides of the gate 13B. In this manner, the gate 138 serves as a partition to separate one side of the skid 10B from the other side, in order that parts of different size, shape, color or the like, may be initially segregated and remain so during transit and storage. Of course, any number of partitions 13B may be employed to meet a particular need, as long as there is clearance space remaining interiorly of the skid 108. Although not shown in this FIG., it will be apparent that another end gate constructed like a reverse image of the illustrated end gate 13 could be provided on the open end of the skid, so as to provide at least two walled compartments in a single skid.

Since the edge of the deck 11B is not available to reinforce the partition 138 at the bottom edge thereof, it is preferred to provide one or more recesses 25 as shown in FIG. 8 which are engageable by a corresponding number of protrusions such as the protrusions 24 shown in FIG. 7. In order to permit the partition 138 to lie fiat against the top of the deck 11 when said partition is in its stored position, a reinforcing means such as lip 23 (which was provided in the end gate 13) cannot be provided on partition 13B. The need for such a reinforcing lip, however, is not as great for internal members on a skid, since they are protected against bumps and the like by the external members. Hence, such partitions 13B typically have a longevity which matches that of the reinforced, but exposed, gates 13.

By reference to the longevity of the component parts of the skid, it is not intended to suggest that the parts are fragile, or unusually susceptible to breakage, such that they might have a short service life. Rather, it is in recognition of the fact that such material-handling skids are frequently subjected to extremely rough treatment, and not necessarily through careless use, that prompts mention of the longevity of the instant skids. That is, skids of the type being described herein are generally intended to carry truly heavy loads. For example, a typical steel skid 108 having a width of 36 inches and a deck thickness of about 2 inches is typically rated at 3,000 lb. capacity. If a set of tools, dies or the like, weighing 3,000 lbs. or so must be picked up from a press and transferred to a skid for further transportation or storage, it will probably be difficult to gently place such tools on the deck of the skid. Accordingly, the skid must be capable of occasionally enduring relatively severe jolts during loading and transport. In view of the relatively severe treatment that can be anticipated for such skids, it is believed prudent to evaluate the expected longevity of each of the elements that make up a skid. Based on this criterion, it is believed that the elements of the skid described herein are particularly well adapted to provide a long life under severe working conditions.

Since the configuration of the skids described herein can be changed from the skids'with two upstanding sidewalls to skids with three or four upstanding sidewalls at will, these skids should satisfy most all needs within the average factory, excluding those skids that are devoid of any walls (which are used for flat stock and the like). Thus, when a machinist, for example, is producing parts having a length somewhat in excess of the standard skid length, either of the end gates of a skid having two end gates can be moved from an upstanding position to a stored position, such that the parts may lie flat on the deck 11 even if they do extend over one edge of the deck. If there is believed to be some risk that the parts may bounce off the skid in the absence of some end restraint, the configuration of the slot 16 illustrated in FIG. 3 imparts still another advantage to the gate 13. Instead of rotating a gate 13 (as viewed in FIG. 3) counterclockwise to a position as shown in FIG. 5, the gate may be moved clockwise by an appropriate amount (usually less than 90) and the parts inserted from the end of the skid. If this is done, the bottom edge 20 of the gate l3 can then be lowered to rest on top of those parts that extend beyond the edge of the base 11, so as to serve as a damper against excessive movement of the parts.

The gates are never removed from the skid, except for repairs; they are merely stored in a place where they do not interfere with material handling. When long parts are removed at a work station within the factory, all that is required to return the skids to a configuration for holding small parts is to grasp the gate 13 with a persons hand, pull the gate outward and away from the interior of the skid, and then tilt the gate upward until the bottom edge has cleared the edge of the deck 11; the gate can then be dropped a small distance until it comes to rest securely in its upstanding position. The dominant advantage of never removing the gates from their associated skids is that they can never be misplaced or left behind at one part of the factory when the skids are transported to another part of the factory. Thus, when the end gates are needed, they are always available.

A further advantage is that existing skids with two upstanding sidewalls can be readily modified in accordance with the teachings herein so as to increase the utility of such skids. All that is required is to provide a means for permanently affixing a gate as described herein to the sidewalls. Such means may include a pair of studs for each of the gates, one of which studs extends inwardly from each sidewall so as to be coaxially aligned with the opposite one of the pair of studs. Each of such studs is preferably affixed to the respective sidewall at a point which is equidistant from the side edge of the sidewall and the top of the base, as shown in FIG. 10. When the means for affixing the gate is prepared, the gate is placed into position on the deck, and the studs are installed such that they extend through the slots in the end plates of the gate. Another advantage of the improvement taught herein is that the gates do not interfere with the normal capacity of such skids of being stacked, one upon another.

While only a principal embodiment of the invention, together with some modifications thereof, have been described in detail herein and shown in the accompanying drawings, it will be evident that various further modifications are possible in the arrangement and construction of the components without departing from the scope of the invention.

I claim:

I. A material-handling skid, comprising:

a substantially rectangular platform having a generally smooth upper surface;

a fixed, upstanding sidewall extending from each of two opposite sides of the platform; I

at least one gate permanently affixed to and extending between the two sidewalls; and

means rendering each such gate selectively movable between an upstanding position and a stored position wherein the sidewalls remain upstanding and the bulk of the gate lies fiat against the top surface of the platform, whereby material being handled may be placed on top of the gate when it is in its stored position.

2. The material-handling skid as claimed in claim 1, and further comprising:

at least one pair of studs, one of which studs extends inwardly from each sidewall so as to be coaxially aligned with the opposite one of the pair of studs, and wherein said gate has a main plate having two ends separated by a distance slightly less than the distance between the two sidewalls; and

an end plate attached to each end of the main plate so as to be perpendicular to the main plate, with each end plate having a slot through which one of the aforementioned studs extends, said slot having a configuration which prevents horizontal movement of the end plate when the main plate is in an upstanding position, and which prevents vertical movement of the end plate when the main plate is in a stored position wherein the main plate lies flat against the platfonn, and said slot further having a configuration which permits the main plate to be selectively moved between its upstanding and its stored position by selective rotation and translation of the end plates with respect to their associated studs.

3. The material-handling skids as claimed in claim 2, wherein at least one gate extends between the two sidewalls at terminal portions thereof so as to functionally form a continuation of said sidewalls, and wherein said main plate has a bottom edge which engages the platform when the main plate is in its upstanding position so as to inhibit horizontal movement of the main plate toward the interior of the skid.

4. The material-handling skid as claimed in claim 2, wherein at least one gate extends between the two sidewalls at a location other than the terminal portions of said sidewalls, such that portions of said platform lie on opposite sides of said gauge 5. The material-handling skid as claimed in claim 2, wherein the slot has a generally V configuration with the included angle being approximately 135, with one leg of the V extending parallel to the main plate and the other leg extending toward the bottom edge of the main plate, and the apex of the V being so positioned as to coincide with the longitudinal axis of that stud which is associated with the respective slot when the gate is in its upstanding position.

6. The material-handling skid as claimed in claim 2, and further comprising a lip extending from the top edge of said main plate in a plane other than the plane of the main plate, and said lip being adapted to bear against the platform edge when the main plate is in its stored position.

7. The material-handling skid as claimed in claim 6 wherein the lip is integral with and extends perpendicularly from the main plate in a direction away from the end plates.

8. In combination with a container having a substantially rectangular base and two upstanding sidewalls extending from opposite sides of the base, a gate for selectively closing the gap between the two walls so as to functionally create a continuation of the walls, comprising: v 1

a substantially rectangular main plate having two ends separated by a distance slightly less than the distance between the two sidewalls;

an end plate attached to each end of the substantially rectangular main plate so as to be perpendicular to said main plate, with each end plate having a slot adapted to enclose a stud, said slot having a configuration which prevents horizontal movement of the end plate when the main plate is in an upstanding position, and which prevents vertical movement of the end plate when the main plate is in a stored position wherein the main plate lies fiat against the base, and said slot further having a configuration which permits the main plate to be selectively moved between its upstanding and its stored position by selective rotation and translation of the end plates with respect to associated studs; and

means for permanently affixing the gate to the sidewalls comprising a pair of studs, one of which studs extends inwardly from each sidewall so as to be coaxially aligned with the opposite one of the pair of studs, and each of said studs being affixed to the respective sidewall at a point which is equidistant from the side edge of the sidewall and 'the top of the base. 

1. A material-handling skid, comprising: a substantially rectangular platform having a generally smooth upper surface; a fixed, upstanding sidewall extending from each of two opposite sides of the platform; at least one gate permanently affixed to and extending between the two sidewalls; and means rendering each such gate selectively movable between an upstanding position and a stored position wherein the sidewalls remain upstanding and the bulk of the gate lies flat against the top surface of the platform, whereby material being handled may be placed on top of the gate when it is in its stored position.
 2. The material-handling skid as claimed in claim 1, and further comprising: at least one pair of studs, one of which studs extends inwardly from each sidewall so as to be coaxially aligned with the opposite one of the pair of studs, and wherein said gate has a main plate having two ends separated by a distance slightly less than the distance between the two sidewalls; and an end plate attached to each end of the main plate so as to be perpendicular to the main plate, with each end plate having a slot through which one of the aforementioned studs extends, said slot having a configuration which prevents horizontal movement of the end plate when the main plate is in an upstanding position, and which prevents vertical movement of the end plate when the main plate is in a stored position wherein the main plate lies flat against the platform, and said slot further having a configuration which permits the main plate to be selectively moved between its upstanding and its stored position by selective rotation and translation of the end plates with respect to their associated studs.
 3. The material-handling skids as claimed in claim 2, wherein at least one gate extends between the two sidewalls at terminal portions thereof so as to functionally form a continuation of said sidewalls, and wherein said main plate has a bottom edge which engages the platform when the main plate is in its upstanding position so as to inhibit horizontal movement of the main plate toward the interior of the skid.
 4. The material-handling skid as claimed in claim 2, wherein at least one gate extends between the two sidewalls at a location other than the terminal portions of said sidewalls, such that portions of said platform lie on opposite sides of said gauge
 5. The material-handling skid as claimed in claim 2, wherein the slot has a generally ''''V'''' configuration with the included angle being approximately 135*, with one leg of the ''''V'''' extending parallel to the main plate and the other leg extending toward the bottom edge of the main plate, and the apex of the ''''V'''' being so positioned as to coincide with the longitudinal axis of that stud which is associated with the respective slot when the gate is in its upstanding position.
 6. The material-handling skid as claimed in claim 2, and further comprising a lip extending from the top edge of said main plate in a plane other than the plane of the main plate, and said lip being adapted to bear against the platform edge when the main plate is in its stored position.
 7. The material-handling skid as claimed in claim 6 wherein the lip is integral with and extends perpendicularly from the main plate in a direction away from the end plates.
 8. In combination with a container having a substantially rectangular base and two upstanding sidewalls extending from opposite sides of the base, a gate for selectively closing the gap between the two walls so as to functionally create a continuation of the walls, comprising: a substantially rectangular main plate having two ends separated by a distance slightly less than the distance between the two sidewalls; an end plaTe attached to each end of the substantially rectangular main plate so as to be perpendicular to said main plate, with each end plate having a slot adapted to enclose a stud, said slot having a configuration which prevents horizontal movement of the end plate when the main plate is in an upstanding position, and which prevents vertical movement of the end plate when the main plate is in a stored position wherein the main plate lies flat against the base, and said slot further having a configuration which permits the main plate to be selectively moved between its upstanding and its stored position by selective rotation and translation of the end plates with respect to associated studs; and means for permanently affixing the gate to the sidewalls comprising a pair of studs, one of which studs extends inwardly from each sidewall so as to be coaxially aligned with the opposite one of the pair of studs, and each of said studs being affixed to the respective sidewall at a point which is equidistant from the side edge of the sidewall and the top of the base. 